Sang Yoon Lee

Toulouse School of Economics
21 Allee de Brienne
31000 Toulouse, FRANCE


NBER Working Papers and Publications

February 2018Computerizing Industries and Routinizing Jobs: Explaining Trends in Aggregate Productivity
with Sangmin Aum, Yongseok Shin: w24357
Aggregate productivity growth in the U.S. has slowed down since the 2000s. We quantify the importance of differential productivity growth across occupations and across industries, and the rise of computers since the 1980s, for the productivity slowdown. Complementarity across occupations and industries in production shrinks the relative size of those with high productivity growth, reducing their contributions toward aggregate productivity growth, resulting in its slowdown. We find that such a force, especially the shrinkage of occupations with above-average productivity growth through “routinization,” was present since the 1980s. Through the end of the 1990s, this force was countervailed by the extraordinarily high productivity growth in the computer industry, of which output became an inc...
March 2017Horizontal and Vertical Polarization: Task-Specific Technological Change in a Multi-Sector Economy
with Yongseok Shin: w23283
We analyze the effect of technological change in a novel framework that integrates an economy's skill distribution with its occupational and industrial structure. Individuals become managers or workers based on their managerial vs. worker skills, and workers further sort into a continuum of tasks (occupations) ranked by skill content. Our theory dictates that faster technological progress for middle-skill tasks not only raises the employment shares and relative wages of lower- and higher-skill occupations among workers (horizontal polarization), but also raises those of managers over workers as a whole (vertical polarization). Both dimensions of polarization are faster within sectors that depend more on middle-skill tasks and less on managers. This endogenously leads to faster TFP growth o...
November 2015The Option Value of Human Capital: Higher Education and Wage Inequality
with Yongseok Shin, Donghoon Lee: w21724
Going to college is a risky investment in human capital. However, we highlight two options inherently embedded in college education that mitigate this risk: (i) college students can quit without completing four-year degrees after learning about their post-graduation wages and (ii) college graduates can take jobs that do not require four-year degrees (i.e., underemployment). These options reduce the chances of falling in the lower end of the wage distribution as a college graduate, rendering standard mean-variance calculations misleading. We show that the interaction between these options and the rising wage dispersion, especially among college graduates, is key to understanding the muted response of college enrollment and graduation rates to the substantial increase in the college wage pre...
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